B-60565 - Enable JMX Metrics for Tomcat Connection Pools

[usnavi]

NOTE: this pull request requires on a corresponding one from puppet-atomhopper. Don't accept this until the other one has been accepted.

• Using Metrics 3.0 as its better documented than previous versions. We might want to upgrade other components using earlier versions to 3.0.
• Added TomcatJdbcPoolGraphiteReporter which takes a map of DataSource beans and does the following:
  • Registers the associated MBeans with the JVM
  • Registers the associated MBeans with Metrics
  • Enables Metrics GraphiteReporter
• TomcatJdbcPoolGraphiteReporter is configured through application-context.xml

[shintasmith]

Other than the commented out ConsoleReporter, the rest looks good.